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1.
A. P. Farrell P. L. Lutz 《Journal of comparative physiology. B, Biochemical, systemic, and environmental physiology》1975,102(2):159-166
Summary On adapting brackish waterAnguilla anguilla to fresh water it was noted that, while the plasma sodium, magnesium,pCO2 and pH were held reasonably constant, there was a substantial fall in chloride concentration (–33 mEq). The gradient of the linear correlations between plasma sodium and chloride also fell (brackish water gradient=0.92, fresh water gradient=0.21) indicating that a new pattern of plasma ion interrelationships was being established. Comparison with plasma Na/Cl ion ratios from other fishes suggested that this phenomenon was peculiar toA. anguilla. Corresponding with the very low plasma chloride levels plasma bicarbonate was four to five times that found in other fishes, and this was thought related to the finding that the haematocrit value almost doubled during adaptation to fresh water. In fresh water adapted fish a fall in plasma chloride was associated with a rise in plasma bicarbonate, however the charge compensation effect of this response was only partial as summing the common plasma cations and anions left an anion deficit of about 34 mEq to be accounted for. 相似文献
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We show that expanded bed protein A affinity chromatography using Streamline rProtein A media is an efficient method for purifying a recombinant humanized monoclonal antibody from unclarified Chinese hamster ovary cell culture fluid and that it provides purification performance comparable to using a packed bed. We determined that the dynamic capacity of the expanded bed media is related to flow rate (measured in column volumes per hour) by a power function, which allows a high capacity at a low flow rate. At 250 cm h-1 with a 25 cm bed height (10 column volumes h-1), the dynamic capacity is 30 g l-1. The yield and purity (measured by the amount of host cell proteins, DNA, SDS-PAGE, and turbidity) of the antibody purified by expanded bed is comparable to the yield and purity obtained on a standard packed bed method using Prosep A media. 相似文献
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Cephalometric measurements on 50 English and 50 Indian adults, equally divided as regards sex, were compared for sex and group difference. Evaluation of the average measurements indicated that the female facial size was generally smaller than the male: the Indian face was not prognathic but was smaller and had smaller facial and gonial angles, and the lower incisor was proclined as compared with the English face. A statistical analysis using the Generalized T2-test and Discriminatory Analysis brought out these differences very convincingly, and with nearly 80% accuracy it was possible to classify the individuals to their correct sex and Indian or English group. Incidentally it was found that the Sella Nasion Plane, Maxillary Plane and Frankfort Plane are all equally suitable for assessing the upper incisor inclination. 相似文献
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Eirik Rindal Geir E. E. Søli Jostein Kjærandsen & Lutz Bachmann 《Zoologica scripta》2007,36(4):327-335
The phylogenetic relationships within the fungus gnat tribe Exechiini have been left unattended for many years. Recent studies have not shed much light on the intergeneric relationship within the tribe. Here the first attempt to resolve the phylogeny of the tribe Exechiini using molecular markers is presented. The nuclear 18S and the mitochondrial 16S, and cytochrome oxidase subunit I (COI) genes were successfully sequenced for 20 species representing 15 Exechiini genera and five outgroup genera. Bayesian, maximum parsimony and maximum likelihood analyses revealed basically congruent tree topologies and the monophyly of Exechiini, including the genus Cordyla , is confirmed. The molecular data corroborate previous morphological studies in several aspects. Cordyla is found in a basal clade together with Brachypeza , Pseudorymosia and Stigmatomeria . The splitting of the genera Allodiopsis s.l. and Brevicornu s.l. as well as the sistergroup relationship of Exechia and Exechiopsis is also supported. The limited phylogenetic information provided by morphological characters is mirrored in the limited resolution of the molecular markers used in this study. Short internal and long-terminal branches obtained may indicate a rapid radiation of the Exechiini genera during a short evolutionary period. 相似文献